n. 25B6; adjective
a madcap scheme : RECKLESS, rash, foolhardy, foolish, hare-brained, wild, hasty, imprudent, ill-advised; informal crazy, crackpot, crackbrained.
a madcap comedy : ZANY, eccentric, unconventional.
25B6; noun she was a boisterous madcap : ECCENTRIC, crank, madman/madwoman, maniac, lunatic; oddity, character, individual; informal crackpot, oddball, weirdo, loony, nut; Brit. informal nutter; N. Amer. informal screwball.